The invention relates to a feed apparatus for feeding capsular cartridges into a drilled hole, the apparatus being intended to be arranged in conjunction with a rock drill apparatus and comprising tubular spaces arranged on at least one perimeter of a rotatable cylindrical cartridge magazine, the cartridge to be fed being insertable in the tubular spaces, i.e. charge tubes, and means for feeding pressure air into the rear end of the charge tubes indexed to the feed position so as to convey the cartridges loaded into the charge tubes to the drilled hole by means of pressure air.
In rock drilling, soldered anchor bolts are used to strengthen the rock and to prevent blocks from breaking off. The bolts can be soldered, for example, using cement mass, adhesive or a soldering material comprising two or more components. In practice it is two-component epoxy or polyester-based soldering materials that are used in the soldering, since their curing time can be easily adjusted by changing the quantity or characteristics of the curing agent. Further, such soldering materials provide good support, and they help to prevent the bolt from corroding in the hole. When a two-component soldering material is used, a necessary number of so-called resin cartridges are first arranged in the drill hole, after which an anchor bolt is arranged in the hole. If the resin cartridges have not yet been broken, the bolt breaks the cartridges, whereby the soldering material contained in the cartridges mixes with the curing agent, and the soldering material starts to cure. The soldering of the resin cartridges thus comprises three steps: drilling of a hole, feeding of the cartridges into the hole, and insertion of a bolt into the hole.
At present the resin cartridges are introduced into the drilled holes either manually or by firing them individually into the drilled hole by means of pressure air. Since the drilling is otherwise performed mechanically and is highly automated, manual introduction of the cartridges is not sensible: it is much too slow and may jeopardize occupational safety. Because of this, one has developed an apparatus which is operated by pressure air and by which the cartridges can be shot individually from the cabin of the drill apparatus to the drilled hole. The cartridges are loaded individually into a cartridge chamber, from which they are pushed by pressure air to a feed hose and along the hose to a nozzle located at the outermost end of the hose. The tip of the nozzle is aligned with the drilled hole so that when a cartridge is shot, it penetrates into the hole without any difficulty. The resin cartridge is a tubular element closed at its both ends. The case of the element is usually made of tubular plastic film, and a soldering material is extruded inside the element. A curing agent is arranged within the case separately, after which the ends of the cartridge are closed. When such a cartridge is shot to a hole at a high rate, it usually breaks in the hole so that the curing agent and the actual soldering material mix and the curing starts. It is, however, rather laborious and slow to use this kind of apparatus, for the cartridges are here loaded and shot manually one by one. Sometimes in the case of long anchor bolts or bolts with otherwise special demands it may be necessary to fire several resin cartridges into one and the same hole, naturally depending on the size of the resin cartridges. It takes rather a long time to feed so many cartridges by an apparatus that fires cartridges individually, and so a long curing time for resin is needed. Further, since the principle of operation makes it necessary to place the apparatus in the control cabin of the rock drill apparatus, the user risks being exposed to harmful gases expelled from leaking or breaking cartridges. On the plea of occupational safety, many countries have therefore prohibited the handling of cartridges in a closed space. Another drawback of the apparatus is that space must be reserved for storing cartridges in an even otherwise confined cabin so that the cartridges will be close at hand when they need to be shot.
The object of the invention is to provide a better and more efficient feed apparatus for pneumatic feeding of capsular cartridges into a drilled hole.
The feed apparatus of the invention is characterized in that the feed apparatus comprises a rotating apparatus to turn the cartridge magazine about its longitudinal axis to a predefined position so that at least one tubular space is in the feed position, i.e. aligns with a feed hose leading to the drilled hole, and that the feed apparatus comprises sealing means for sealing the front and rear ends of the charge tube indexed to the feed position.
The essential idea of the invention is that the feed apparatus comprises a rotatable roll-like cartridge magazine that comprises tubular spaces on one or more of its perimeters, the cartridges being loaded into these spaces before the pneumatic feed, i.e. the xe2x80x98shotxe2x80x99. To fire a cartridge, the tubular space that contains the cartridge to be fed at a given moment is indexed to the feed position by the magazine-rotating apparatus, after which the contents of the tube is fed along the feed hose into the drill hole by means of pressure air. The essential idea of a preferred embodiment of the invention is that the cartridge magazine comprises separate charge tubes that are open at their both ends. The essential idea of a second preferred embodiment is that charge tubes are arranged on at least two coaxial perimeters. The idea of a third preferred embodiment is that the cartridge magazine is arranged vertically, so that gravitation can be used to help to move the cartridges.
The advantage of the invention is that the cartridges can be fed automatically without touching them by hand. There is less need to handle the cartridges, and so the occupational safety is improved. In addition, the cartridges need not be handled at all in the control cabin, for the cartridges are loaded into the magazine outside the cabin, and the actual firing has been automated. No fumes are expelled from the resin cartridges or the like to the cabin at any point, and no space needs to be reserved for the handling or storage of the cartridges. It is also clear that the automated firing is much quicker and more efficient than individual firing of the cartridges, not to mention manual loading. With the apparatus of the invention, the contents of a charge tube can be shot in about 2 or 3 seconds. When charge tubes are arranged on more than one perimeter, the capacity of the magazine is naturally higher. Further, there is always more than one charge tube ready in the feed position for the firing, whereby several cartridges can be shot, if desired, by a single indexing action, i.e. turning of the cartridge magazine to a predefined position. The time needed for the indexing is thus shorter. The control system of the apparatus according to the invention also allows varied and flexible firing of the cartridges, so that exactly the correct number of desired cartridges can be shot automatically to each hole. The feed apparatus of the invention is particularly well suited for use in conjunction with a bolting device in which a rock drill, a feed device for a soldering material and a feed device for bolts are arranged in the bolting device so that they can be indexed, whereby the bolting steps can be carried out in quick succession.